Below is the NRL response to the 29 December 2009 Boston Globe article entitled “Potent Fuel at MIT Reactor Makes Uneasy Politics” by Bryan Bender of the Globe Washington DC office.
Certain basic facts were available to the Globe prior to publication of the article, but did not appear clearly in the article.
One premise of the article was that the MIT Reactor (MITR) could be converted immediately to low-enriched uranium (LEU) fuel if only MIT were willing to accept a small (~10%) decrease in the reactor’s performance. While this statement is true for many low-power university reactors, it is not true for the MITR. Also comments in the article on the security of our fuel inventory are highly misleading. In particular, the following should be noted:
1. The MITR has a very compact core, as do several of the other high performance research reactors including the ones at Missouri-Columbia, NIST, and at Oak Ridge National Laboratory. These reactors can NOT attain criticality using the LEU fuel that has been developed by the Department of Energy (DOE). It is not a question of accepting a small decrement in performance. Conversion with the existing LEU would mean that the MITR could no longer operate. The existing LEU has a density of 4.8 grams/cc. For the MITR to maintain criticality and a reasonable fuel cycle, a density of about 14 grams/cc is required. DOE has candidate fuels that will achieve this density under development. However, efficacy has yet to be shown — tests of the material’s properties are still underway at the Advanced Test Reactor in Idaho.
2. MIT is committed to convert to LEU and has been so committed in writing with the Nuclear Regulatory Commission since the mid 1980s when the LEU conversion effort was initiated in the U.S. We have not, as the article stated, blocked or delayed the program. We have pointed out the need for a high-density LEU fuel that would enable all the high performance reactors to maintain criticality. Conversion planning is currently a major activity at the MIT Nuclear Reactor Laboratory, but again it hinges on the DOE development of a suitable fuel, followed by NRC certification. We strongly concur with current plans to implement the new fuel in 2014.
3. Our existing highly-enriched uranium (HEU) fuel is safe from diversion. The MITR has always had excellent security and is constantly evaluating and upgrading security. Fresh fuel is brought in the day of a planned refueling under enhanced security, and immediately placed in the reactor core for irradiation. Thus, there is almost never any fresh fuel on site, and it is limited to much less than the amount needed to make a weapon. As regards irradiated fuel, it is highly radioactive. NRC defines fuel to be “self-protecting” in the sense that it is sufficiently radioactive so that anyone stealing it would suffer serious health consequences if it exceeds 100 rads per hour at one meter. One can debate the adequacy of this level. For someone who does not value their life, it is not a deterrent. However, MITR fuel greatly exceeds this level and would cause serious, often debilitating, illness and/or death if anyone were to remove it without massive shields that could not be concealed.